State governments decide the laws on whether or not gun shows within their respective state must conduct a background check

Really?

So why did the ATF put out this publication?

http://www.atf.gov/publications/download/i/atf-i-5300-23a.pdf

Note:

The conduct of business rules apply to FFL’s operating at in state gun shows as they do at your licensed business premises with one exception: you must document on the ATF Form 4473 (5300.9) the location of the gun show where the sale or other disposition took place. In pertinent part, FFL’s operating at in state gun shows may dispose of handguns to residents of the same state if the individual is not otherwise disqualified from receiving the handgun. Dispose of long guns to residents of any state if the individual is not otherwise prohibited from receiving a long gun and the sale complies with the laws of the state where the purchaser resides. And dispose of any firearms to any FFL and acquire firearms from any FFL licensed in the same state as the gun show and your licensed business premises as well as from any non-licensed individual. Acquiring firearms from an out of state FFL would place the selling FFL in violation of the Gun Control Act as he or she would be considered to be dealing away from her or his licensed business premises.

FFL’s may not make any sales of firearms to anyone at out of state gun shows; however, FFL’s may acquire firearms from other FFL’s whose licensed business is in the same state as the gun show, display and take orders for firearms, and acquire and sell curio’s and relics to any FFL licensee.

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